Paper Info
Title
Thermal fatigue in solder joints of Ag-Pd and Ag-Pt metallized LTCC modules.
Abstract
The fatigue behaviour of joints between ceramic LTCC modules and FR-4 boards was investigated using thermal cycling tests at temperature intervals of 0 degreesC - 100 degreesC and -40 degreesC - 125 degreesC and analysis of the cycled modules using scanning acoustic microscopy and SEM/EDS. The assemblies were fabricated with Ag-Pd and Ag-Pt metallized pads on LTCC. Fatigue cracks initiated in the solder region of the Ag-Pd metallized LTCC modules, but propagated later in the ceramic module. Propagation was remarkably retarded by Ag-filled vias located under the pads on LTCC. The final cracks that caused an electrical failure in the modules crossed the root region of the vias along the thick Ag3Sn+PdSn4 layer located in this region. The joints of the Ag-Pt metallized modules passed the resistance measurement in both tests. However, they also showed crack growth that initiated on the LTCC/metallization interface, propagated in the ceramic, but was retarded by the vias. These vias were resistant to fracture, since only a thin Ag3Sn layer (approximate to 1 mum) existed in their root region. (C) 2001 Elsevier Science Ltd. All rights reserved.
Year
DOI
Venue
2001
10.1016/S0026-2714(01)00163-9
Microelectronics Reliability
DocType
Volume
Issue
Journal
41
9
ISSN
Citations 
PageRank 
0026-2714
2
0.94
References 
Authors
0
5
Name
Order
Citations
PageRank
R. Rautioaho172.10
O. Nousiainen272.10
S. Leppävuori320.94
J. Lenkkeri420.94
T. Jaakola520.94